Dozens of combatants converged in McCarren Park yesterday to beat each other mercifully as a crowd of bystanders shouted words of encouragement. The Cardboard Tube Fighting League came to north Brooklyn as planned, drawing competitors in all sorts of corrugated armor and costume to hit one another with regulation cardboard â€œswords.â€ Besides a lot of trees, it’s pretty safe to say nobody was hurt. A video of the cardboard melee is after the jump.